
; (function () {
  var UPNG = {};

  // Make available for import by `require()`
  var pako;
  if (typeof module == "object") { module.exports = UPNG; } else { window.UPNG = UPNG; }
  if (typeof require == "function") { pako = require("./pako"); } else { pako = window.pako; }
  function log() { if (typeof process == "undefined" || process.env.NODE_ENV == "development") console.log.apply(console, arguments); }
  (function (UPNG, pako) {




    UPNG.toRGBA8 = function (out) {
      var w = out.width, h = out.height;
      if (out.tabs.acTL == null) return [UPNG.toRGBA8.decodeImage(out.data, w, h, out).buffer];

      var frms = [];
      if (out.frames[0].data == null) out.frames[0].data = out.data;

      var img, empty = new Uint8Array(w * h * 4);
      for (var i = 0; i < out.frames.length; i++) {
        var frm = out.frames[i];
        var fx = frm.rect.x, fy = frm.rect.y, fw = frm.rect.width, fh = frm.rect.height;
        var fdata = UPNG.toRGBA8.decodeImage(frm.data, fw, fh, out);

        if (i == 0) img = fdata;
        else if (frm.blend == 0) UPNG._copyTile(fdata, fw, fh, img, w, h, fx, fy, 0);
        else if (frm.blend == 1) UPNG._copyTile(fdata, fw, fh, img, w, h, fx, fy, 1);

        frms.push(img.buffer); img = img.slice(0);

        if (frm.dispose == 0) { }
        else if (frm.dispose == 1) UPNG._copyTile(empty, fw, fh, img, w, h, fx, fy, 0);
        else if (frm.dispose == 2) {
          var pi = i - 1;
          while (out.frames[pi].dispose == 2) pi--;
          img = new Uint8Array(frms[pi]).slice(0);
        }
      }
      return frms;
    }
    UPNG.toRGBA8.decodeImage = function (data, w, h, out) {
      var area = w * h, bpp = UPNG.decode._getBPP(out);
      var bpl = Math.ceil(w * bpp / 8);	// bytes per line

      var bf = new Uint8Array(area * 4), bf32 = new Uint32Array(bf.buffer);
      var ctype = out.ctype, depth = out.depth;
      var rs = UPNG._bin.readUshort;


      if (ctype == 6) { // RGB + alpha
        var qarea = area << 2;
        if (depth == 8) for (var i = 0; i < qarea; i++) { bf[i] = data[i];  /*if((i&3)==3 && data[i]!=0) bf[i]=255;*/ }
        if (depth == 16) for (var i = 0; i < qarea; i++) { bf[i] = data[i << 1]; }
      }
      else if (ctype == 2) {	// RGB
        var ts = out.tabs["tRNS"], tr = -1, tg = -1, tb = -1;
        if (ts) { tr = ts[0]; tg = ts[1]; tb = ts[2]; }
        if (depth == 8) for (var i = 0; i < area; i++) {
          var qi = i << 2, ti = i * 3; bf[qi] = data[ti]; bf[qi + 1] = data[ti + 1]; bf[qi + 2] = data[ti + 2]; bf[qi + 3] = 255;
          if (tr != -1 && data[ti] == tr && data[ti + 1] == tg && data[ti + 2] == tb) bf[qi + 3] = 0;
        }
        if (depth == 16) for (var i = 0; i < area; i++) {
          var qi = i << 2, ti = i * 6; bf[qi] = data[ti]; bf[qi + 1] = data[ti + 2]; bf[qi + 2] = data[ti + 4]; bf[qi + 3] = 255;
          if (tr != -1 && rs(data, ti) == tr && rs(data, ti + 2) == tg && rs(data, ti + 4) == tb) bf[qi + 3] = 0;
        }
      }
      else if (ctype == 3) {	// palette
        var p = out.tabs["PLTE"], ap = out.tabs["tRNS"], tl = ap ? ap.length : 0;
        if (depth == 1) for (var y = 0; y < h; y++) {
          var s0 = y * bpl, t0 = y * w;
          for (var i = 0; i < w; i++) { var qi = (t0 + i) << 2, j = ((data[s0 + (i >> 3)] >> (7 - ((i & 7) << 0))) & 1), cj = 3 * j; bf[qi] = p[cj]; bf[qi + 1] = p[cj + 1]; bf[qi + 2] = p[cj + 2]; bf[qi + 3] = (j < tl) ? ap[j] : 255; }
        }
        if (depth == 2) for (var y = 0; y < h; y++) {
          var s0 = y * bpl, t0 = y * w;
          for (var i = 0; i < w; i++) { var qi = (t0 + i) << 2, j = ((data[s0 + (i >> 2)] >> (6 - ((i & 3) << 1))) & 3), cj = 3 * j; bf[qi] = p[cj]; bf[qi + 1] = p[cj + 1]; bf[qi + 2] = p[cj + 2]; bf[qi + 3] = (j < tl) ? ap[j] : 255; }
        }
        if (depth == 4) for (var y = 0; y < h; y++) {
          var s0 = y * bpl, t0 = y * w;
          for (var i = 0; i < w; i++) { var qi = (t0 + i) << 2, j = ((data[s0 + (i >> 1)] >> (4 - ((i & 1) << 2))) & 15), cj = 3 * j; bf[qi] = p[cj]; bf[qi + 1] = p[cj + 1]; bf[qi + 2] = p[cj + 2]; bf[qi + 3] = (j < tl) ? ap[j] : 255; }
        }
        if (depth == 8) for (var i = 0; i < area; i++) { var qi = i << 2, j = data[i], cj = 3 * j; bf[qi] = p[cj]; bf[qi + 1] = p[cj + 1]; bf[qi + 2] = p[cj + 2]; bf[qi + 3] = (j < tl) ? ap[j] : 255; }
      }
      else if (ctype == 4) {	// gray + alpha
        if (depth == 8) for (var i = 0; i < area; i++) { var qi = i << 2, di = i << 1, gr = data[di]; bf[qi] = gr; bf[qi + 1] = gr; bf[qi + 2] = gr; bf[qi + 3] = data[di + 1]; }
        if (depth == 16) for (var i = 0; i < area; i++) { var qi = i << 2, di = i << 2, gr = data[di]; bf[qi] = gr; bf[qi + 1] = gr; bf[qi + 2] = gr; bf[qi + 3] = data[di + 2]; }
      }
      else if (ctype == 0) {	// gray
        var tr = out.tabs["tRNS"] ? out.tabs["tRNS"] : -1;
        if (depth == 1) for (var i = 0; i < area; i++) { var gr = 255 * ((data[i >> 3] >> (7 - ((i & 7)))) & 1), al = (gr == tr * 255) ? 0 : 255; bf32[i] = (al << 24) | (gr << 16) | (gr << 8) | gr; }
        if (depth == 2) for (var i = 0; i < area; i++) { var gr = 85 * ((data[i >> 2] >> (6 - ((i & 3) << 1))) & 3), al = (gr == tr * 85) ? 0 : 255; bf32[i] = (al << 24) | (gr << 16) | (gr << 8) | gr; }
        if (depth == 4) for (var i = 0; i < area; i++) { var gr = 17 * ((data[i >> 1] >> (4 - ((i & 1) << 2))) & 15), al = (gr == tr * 17) ? 0 : 255; bf32[i] = (al << 24) | (gr << 16) | (gr << 8) | gr; }
        if (depth == 8) for (var i = 0; i < area; i++) { var gr = data[i], al = (gr == tr) ? 0 : 255; bf32[i] = (al << 24) | (gr << 16) | (gr << 8) | gr; }
        if (depth == 16) for (var i = 0; i < area; i++) { var gr = data[i << 1], al = (rs(data, i << 1) == tr) ? 0 : 255; bf32[i] = (al << 24) | (gr << 16) | (gr << 8) | gr; }
      }
      return bf;
    }



    UPNG.decode = function (buff) {
      var data = new Uint8Array(buff), offset = 8, bin = UPNG._bin, rUs = bin.readUshort, rUi = bin.readUint;
      var out = { tabs: {}, frames: [] };
      var dd = new Uint8Array(data.length), doff = 0;	 // put all IDAT data into it
      var fd, foff = 0;	// frames

      var mgck = [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a];
      for (var i = 0; i < 8; i++) if (data[i] != mgck[i]) throw "The input is not a PNG file!";

      while (offset < data.length) {
        var len = bin.readUint(data, offset); offset += 4;
        var type = bin.readASCII(data, offset, 4); offset += 4;

        if (type == "IHDR") { UPNG.decode._IHDR(data, offset, out); }
        else if (type == "IDAT") {
          for (var i = 0; i < len; i++) dd[doff + i] = data[offset + i];
          doff += len;
        }
        else if (type == "acTL") {
          out.tabs[type] = { num_frames: rUi(data, offset), num_plays: rUi(data, offset + 4) };
          fd = new Uint8Array(data.length);
        }
        else if (type == "fcTL") {
          if (foff != 0) {
            var fr = out.frames[out.frames.length - 1];
            fr.data = UPNG.decode._decompress(out, fd.slice(0, foff), fr.rect.width, fr.rect.height); foff = 0;
          }
          var rct = { x: rUi(data, offset + 12), y: rUi(data, offset + 16), width: rUi(data, offset + 4), height: rUi(data, offset + 8) };
          var del = rUs(data, offset + 22); del = rUs(data, offset + 20) / (del == 0 ? 100 : del);
          var frm = { rect: rct, delay: Math.round(del * 1000), dispose: data[offset + 24], blend: data[offset + 25] };
          out.frames.push(frm);
        }
        else if (type == "fdAT") {
          for (var i = 0; i < len - 4; i++) fd[foff + i] = data[offset + i + 4];
          foff += len - 4;
        }
        else if (type == "pHYs") {
          out.tabs[type] = [bin.readUint(data, offset), bin.readUint(data, offset + 4), data[offset + 8]];
        }
        else if (type == "cHRM") {
          out.tabs[type] = [];
          for (var i = 0; i < 8; i++) out.tabs[type].push(bin.readUint(data, offset + i * 4));
        }
        else if (type == "tEXt") {
          if (out.tabs[type] == null) out.tabs[type] = {};
          var nz = bin.nextZero(data, offset);
          var keyw = bin.readASCII(data, offset, nz - offset);
          var text = bin.readASCII(data, nz + 1, offset + len - nz - 1);
          out.tabs[type][keyw] = text;
        }
        else if (type == "iTXt") {
          if (out.tabs[type] == null) out.tabs[type] = {};
          var nz = 0, off = offset;
          nz = bin.nextZero(data, off);
          var keyw = bin.readASCII(data, off, nz - off); off = nz + 1;
          var cflag = data[off], cmeth = data[off + 1]; off += 2;
          nz = bin.nextZero(data, off);
          var ltag = bin.readASCII(data, off, nz - off); off = nz + 1;
          nz = bin.nextZero(data, off);
          var tkeyw = bin.readUTF8(data, off, nz - off); off = nz + 1;
          var text = bin.readUTF8(data, off, len - (off - offset));
          out.tabs[type][keyw] = text;
        }
        else if (type == "PLTE") {
          out.tabs[type] = bin.readBytes(data, offset, len);
        }
        else if (type == "hIST") {
          var pl = out.tabs["PLTE"].length / 3;
          out.tabs[type] = []; for (var i = 0; i < pl; i++) out.tabs[type].push(rUs(data, offset + i * 2));
        }
        else if (type == "tRNS") {
          if (out.ctype == 3) out.tabs[type] = bin.readBytes(data, offset, len);
          else if (out.ctype == 0) out.tabs[type] = rUs(data, offset);
          else if (out.ctype == 2) out.tabs[type] = [rUs(data, offset), rUs(data, offset + 2), rUs(data, offset + 4)];
        }
        else if (type == "gAMA") out.tabs[type] = bin.readUint(data, offset) / 100000;
        else if (type == "sRGB") out.tabs[type] = data[offset];
        else if (type == "bKGD") {
          if (out.ctype == 0 || out.ctype == 4) out.tabs[type] = [rUs(data, offset)];
          else if (out.ctype == 2 || out.ctype == 6) out.tabs[type] = [rUs(data, offset), rUs(data, offset + 2), rUs(data, offset + 4)];
          else if (out.ctype == 3) out.tabs[type] = data[offset];
        }
        else if (type == "IEND") {
          break;
        }
        //else {  log("unknown chunk type", type, len);  }
        offset += len;
        var crc = bin.readUint(data, offset); offset += 4;
      }
      if (foff != 0) {
        var fr = out.frames[out.frames.length - 1];
        fr.data = UPNG.decode._decompress(out, fd.slice(0, foff), fr.rect.width, fr.rect.height); foff = 0;
      }
      out.data = UPNG.decode._decompress(out, dd, out.width, out.height);

      delete out.compress; delete out.interlace; delete out.filter;
      return out;
    }

    UPNG.decode._decompress = function (out, dd, w, h) {
      if (out.compress == 0) dd = UPNG.decode._inflate(dd);

      if (out.interlace == 0) dd = UPNG.decode._filterZero(dd, out, 0, w, h);
      else if (out.interlace == 1) dd = UPNG.decode._readInterlace(dd, out);
      return dd;
    }

    UPNG.decode._inflate = function (data) { return pako["inflate"](data); }

    UPNG.decode._readInterlace = function (data, out) {
      var w = out.width, h = out.height;
      var bpp = UPNG.decode._getBPP(out), cbpp = bpp >> 3, bpl = Math.ceil(w * bpp / 8);
      var img = new Uint8Array(h * bpl);
      var di = 0;

      var starting_row = [0, 0, 4, 0, 2, 0, 1];
      var starting_col = [0, 4, 0, 2, 0, 1, 0];
      var row_increment = [8, 8, 8, 4, 4, 2, 2];
      var col_increment = [8, 8, 4, 4, 2, 2, 1];

      var pass = 0;
      while (pass < 7) {
        var ri = row_increment[pass], ci = col_increment[pass];
        var sw = 0, sh = 0;
        var cr = starting_row[pass]; while (cr < h) { cr += ri; sh++; }
        var cc = starting_col[pass]; while (cc < w) { cc += ci; sw++; }
        var bpll = Math.ceil(sw * bpp / 8);
        UPNG.decode._filterZero(data, out, di, sw, sh);

        var y = 0, row = starting_row[pass];
        while (row < h) {
          var col = starting_col[pass];
          var cdi = (di + y * bpll) << 3;

          while (col < w) {
            if (bpp == 1) {
              var val = data[cdi >> 3]; val = (val >> (7 - (cdi & 7))) & 1;
              img[row * bpl + (col >> 3)] |= (val << (7 - ((col & 3) << 0)));
            }
            if (bpp == 2) {
              var val = data[cdi >> 3]; val = (val >> (6 - (cdi & 7))) & 3;
              img[row * bpl + (col >> 2)] |= (val << (6 - ((col & 3) << 1)));
            }
            if (bpp == 4) {
              var val = data[cdi >> 3]; val = (val >> (4 - (cdi & 7))) & 15;
              img[row * bpl + (col >> 1)] |= (val << (4 - ((col & 1) << 2)));
            }
            if (bpp >= 8) {
              var ii = row * bpl + col * cbpp;
              for (var j = 0; j < cbpp; j++) img[ii + j] = data[(cdi >> 3) + j];
            }
            cdi += bpp; col += ci;
          }
          y++; row += ri;
        }
        if (sw * sh != 0) di += sh * (1 + bpll);
        pass = pass + 1;
      }
      return img;
    }

    UPNG.decode._getBPP = function (out) {
      var noc = [1, null, 3, 1, 2, null, 4][out.ctype];
      return noc * out.depth;
    }

    UPNG.decode._filterZero = function (data, out, off, w, h) {
      var bpp = UPNG.decode._getBPP(out), bpl = Math.ceil(w * bpp / 8), paeth = UPNG.decode._paeth;
      bpp = Math.ceil(bpp / 8);

      for (var y = 0; y < h; y++) {
        var i = off + y * bpl, di = i + y + 1;
        var type = data[di - 1];

        if (type == 0) for (var x = 0; x < bpl; x++) data[i + x] = data[di + x];
        else if (type == 1) {
          for (var x = 0; x < bpp; x++) data[i + x] = data[di + x];
          for (var x = bpp; x < bpl; x++) data[i + x] = (data[di + x] + data[i + x - bpp]) & 255;
        }
        else if (y == 0) {
          for (var x = 0; x < bpp; x++) data[i + x] = data[di + x];
          if (type == 2) for (var x = bpp; x < bpl; x++) data[i + x] = (data[di + x]) & 255;
          if (type == 3) for (var x = bpp; x < bpl; x++) data[i + x] = (data[di + x] + (data[i + x - bpp] >> 1)) & 255;
          if (type == 4) for (var x = bpp; x < bpl; x++) data[i + x] = (data[di + x] + paeth(data[i + x - bpp], 0, 0)) & 255;
        }
        else {
          if (type == 2) { for (var x = 0; x < bpl; x++) data[i + x] = (data[di + x] + data[i + x - bpl]) & 255; }

          if (type == 3) {
            for (var x = 0; x < bpp; x++) data[i + x] = (data[di + x] + (data[i + x - bpl] >> 1)) & 255;
            for (var x = bpp; x < bpl; x++) data[i + x] = (data[di + x] + ((data[i + x - bpl] + data[i + x - bpp]) >> 1)) & 255;
          }

          if (type == 4) {
            for (var x = 0; x < bpp; x++) data[i + x] = (data[di + x] + paeth(0, data[i + x - bpl], 0)) & 255;
            for (var x = bpp; x < bpl; x++) data[i + x] = (data[di + x] + paeth(data[i + x - bpp], data[i + x - bpl], data[i + x - bpp - bpl])) & 255;
          }
        }
      }
      return data;
    }

    UPNG.decode._paeth = function (a, b, c) {
      var p = a + b - c, pa = Math.abs(p - a), pb = Math.abs(p - b), pc = Math.abs(p - c);
      if (pa <= pb && pa <= pc) return a;
      else if (pb <= pc) return b;
      return c;
    }

    UPNG.decode._IHDR = function (data, offset, out) {
      var bin = UPNG._bin;
      out.width = bin.readUint(data, offset); offset += 4;
      out.height = bin.readUint(data, offset); offset += 4;
      out.depth = data[offset]; offset++;
      out.ctype = data[offset]; offset++;
      out.compress = data[offset]; offset++;
      out.filter = data[offset]; offset++;
      out.interlace = data[offset]; offset++;
    }

    UPNG._bin = {
      nextZero: function (data, p) { while (data[p] != 0) p++; return p; },
      readUshort: function (buff, p) { return (buff[p] << 8) | buff[p + 1]; },
      writeUshort: function (buff, p, n) { buff[p] = (n >> 8) & 255; buff[p + 1] = n & 255; },
      readUint: function (buff, p) { return (buff[p] * (256 * 256 * 256)) + ((buff[p + 1] << 16) | (buff[p + 2] << 8) | buff[p + 3]); },
      writeUint: function (buff, p, n) { buff[p] = (n >> 24) & 255; buff[p + 1] = (n >> 16) & 255; buff[p + 2] = (n >> 8) & 255; buff[p + 3] = n & 255; },
      readASCII: function (buff, p, l) { var s = ""; for (var i = 0; i < l; i++) s += String.fromCharCode(buff[p + i]); return s; },
      writeASCII: function (data, p, s) { for (var i = 0; i < s.length; i++) data[p + i] = s.charCodeAt(i); },
      readBytes: function (buff, p, l) { var arr = []; for (var i = 0; i < l; i++) arr.push(buff[p + i]); return arr; },
      pad: function (n) { return n.length < 2 ? "0" + n : n; },
      readUTF8: function (buff, p, l) {
        var s = "", ns;
        for (var i = 0; i < l; i++) s += "%" + UPNG._bin.pad(buff[p + i].toString(16));
        try { ns = decodeURIComponent(s); }
        catch (e) { return UPNG._bin.readASCII(buff, p, l); }
        return ns;
      }
    }
    UPNG._copyTile = function (sb, sw, sh, tb, tw, th, xoff, yoff, mode) {
      var w = Math.min(sw, tw), h = Math.min(sh, th);
      var si = 0, ti = 0;
      for (var y = 0; y < h; y++)
        for (var x = 0; x < w; x++) {
          if (xoff >= 0 && yoff >= 0) { si = (y * sw + x) << 2; ti = ((yoff + y) * tw + xoff + x) << 2; }
          else { si = ((-yoff + y) * sw - xoff + x) << 2; ti = (y * tw + x) << 2; }

          if (mode == 0) { tb[ti] = sb[si]; tb[ti + 1] = sb[si + 1]; tb[ti + 2] = sb[si + 2]; tb[ti + 3] = sb[si + 3]; }
          else if (mode == 1) {
            var fa = sb[si + 3] * (1 / 255), fr = sb[si] * fa, fg = sb[si + 1] * fa, fb = sb[si + 2] * fa;
            var ba = tb[ti + 3] * (1 / 255), br = tb[ti] * ba, bg = tb[ti + 1] * ba, bb = tb[ti + 2] * ba;

            var ifa = 1 - fa, oa = fa + ba * ifa, ioa = (oa == 0 ? 0 : 1 / oa);
            tb[ti + 3] = 255 * oa;
            tb[ti + 0] = (fr + br * ifa) * ioa;
            tb[ti + 1] = (fg + bg * ifa) * ioa;
            tb[ti + 2] = (fb + bb * ifa) * ioa;
          }
          else if (mode == 2) {	// copy only differences, otherwise zero
            var fa = sb[si + 3], fr = sb[si], fg = sb[si + 1], fb = sb[si + 2];
            var ba = tb[ti + 3], br = tb[ti], bg = tb[ti + 1], bb = tb[ti + 2];
            if (fa == ba && fr == br && fg == bg && fb == bb) { tb[ti] = 0; tb[ti + 1] = 0; tb[ti + 2] = 0; tb[ti + 3] = 0; }
            else { tb[ti] = fr; tb[ti + 1] = fg; tb[ti + 2] = fb; tb[ti + 3] = fa; }
          }
          else if (mode == 3) {	// check if can be blended
            var fa = sb[si + 3], fr = sb[si], fg = sb[si + 1], fb = sb[si + 2];
            var ba = tb[ti + 3], br = tb[ti], bg = tb[ti + 1], bb = tb[ti + 2];
            if (fa == ba && fr == br && fg == bg && fb == bb) continue;
            //if(fa!=255 && ba!=0) return false;
            if (fa < 220 && ba > 20) return false;
          }
        }
      return true;
    }





    UPNG.encode = function (bufs, w, h, ps, dels, forbidPlte) {
      if (ps == null) ps = 0;
      if (forbidPlte == null) forbidPlte = false;

      var nimg = UPNG.encode.compress(bufs, w, h, ps, false, forbidPlte);
      UPNG.encode.compressPNG(nimg, -1);

      return UPNG.encode._main(nimg, w, h, dels);
    }

    UPNG.encodeLL = function (bufs, w, h, cc, ac, depth, dels) {
      var nimg = { ctype: 0 + (cc == 1 ? 0 : 2) + (ac == 0 ? 0 : 4), depth: depth, frames: [] };

      var bipp = (cc + ac) * depth, bipl = bipp * w;
      for (var i = 0; i < bufs.length; i++)
        nimg.frames.push({ rect: { x: 0, y: 0, width: w, height: h }, img: new Uint8Array(bufs[i]), blend: 0, dispose: 1, bpp: Math.ceil(bipp / 8), bpl: Math.ceil(bipl / 8) });

      UPNG.encode.compressPNG(nimg, 4);

      return UPNG.encode._main(nimg, w, h, dels);
    }

    UPNG.encode._main = function (nimg, w, h, dels) {
      var crc = UPNG.crc.crc, wUi = UPNG._bin.writeUint, wUs = UPNG._bin.writeUshort, wAs = UPNG._bin.writeASCII;
      var offset = 8, anim = nimg.frames.length > 1, pltAlpha = false;

      var leng = 8 + (16 + 5 + 4) + (9 + 4) + (anim ? 20 : 0);
      if (nimg.ctype == 3) {
        var dl = nimg.plte.length;
        for (var i = 0; i < dl; i++) if ((nimg.plte[i] >>> 24) != 255) pltAlpha = true;
        leng += (8 + dl * 3 + 4) + (pltAlpha ? (8 + dl * 1 + 4) : 0);
      }
      for (var j = 0; j < nimg.frames.length; j++) {
        var fr = nimg.frames[j];
        if (anim) leng += 38;
        leng += fr.cimg.length + 12;
        if (j != 0) leng += 4;
      }
      leng += 12;

      var data = new Uint8Array(leng);
      var wr = [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a];
      for (var i = 0; i < 8; i++) data[i] = wr[i];

      wUi(data, offset, 13); offset += 4;
      wAs(data, offset, "IHDR"); offset += 4;
      wUi(data, offset, w); offset += 4;
      wUi(data, offset, h); offset += 4;
      data[offset] = nimg.depth; offset++;  // depth
      data[offset] = nimg.ctype; offset++;  // ctype
      data[offset] = 0; offset++;  // compress
      data[offset] = 0; offset++;  // filter
      data[offset] = 0; offset++;  // interlace
      wUi(data, offset, crc(data, offset - 17, 17)); offset += 4; // crc

      // 9 bytes to say, that it is sRGB
      wUi(data, offset, 1); offset += 4;
      wAs(data, offset, "sRGB"); offset += 4;
      data[offset] = 1; offset++;
      wUi(data, offset, crc(data, offset - 5, 5)); offset += 4; // crc

      if (anim) {
        wUi(data, offset, 8); offset += 4;
        wAs(data, offset, "acTL"); offset += 4;
        wUi(data, offset, nimg.frames.length); offset += 4;
        wUi(data, offset, 0); offset += 4;
        wUi(data, offset, crc(data, offset - 12, 12)); offset += 4; // crc
      }

      if (nimg.ctype == 3) {
        var dl = nimg.plte.length;
        wUi(data, offset, dl * 3); offset += 4;
        wAs(data, offset, "PLTE"); offset += 4;
        for (var i = 0; i < dl; i++) {
          var ti = i * 3, c = nimg.plte[i], r = (c) & 255, g = (c >>> 8) & 255, b = (c >>> 16) & 255;
          data[offset + ti + 0] = r; data[offset + ti + 1] = g; data[offset + ti + 2] = b;
        }
        offset += dl * 3;
        wUi(data, offset, crc(data, offset - dl * 3 - 4, dl * 3 + 4)); offset += 4; // crc

        if (pltAlpha) {
          wUi(data, offset, dl); offset += 4;
          wAs(data, offset, "tRNS"); offset += 4;
          for (var i = 0; i < dl; i++)  data[offset + i] = (nimg.plte[i] >>> 24) & 255;
          offset += dl;
          wUi(data, offset, crc(data, offset - dl - 4, dl + 4)); offset += 4; // crc
        }
      }

      var fi = 0;
      for (var j = 0; j < nimg.frames.length; j++) {
        var fr = nimg.frames[j];
        if (anim) {
          wUi(data, offset, 26); offset += 4;
          wAs(data, offset, "fcTL"); offset += 4;
          wUi(data, offset, fi++); offset += 4;
          wUi(data, offset, fr.rect.width); offset += 4;
          wUi(data, offset, fr.rect.height); offset += 4;
          wUi(data, offset, fr.rect.x); offset += 4;
          wUi(data, offset, fr.rect.y); offset += 4;
          wUs(data, offset, dels[j]); offset += 2;
          wUs(data, offset, 1000); offset += 2;
          data[offset] = fr.dispose; offset++;	// dispose
          data[offset] = fr.blend; offset++;	// blend
          wUi(data, offset, crc(data, offset - 30, 30)); offset += 4; // crc
        }

        var imgd = fr.cimg, dl = imgd.length;
        wUi(data, offset, dl + (j == 0 ? 0 : 4)); offset += 4;
        var ioff = offset;
        wAs(data, offset, (j == 0) ? "IDAT" : "fdAT"); offset += 4;
        if (j != 0) { wUi(data, offset, fi++); offset += 4; }
        for (var i = 0; i < dl; i++) data[offset + i] = imgd[i];
        offset += dl;
        wUi(data, offset, crc(data, ioff, offset - ioff)); offset += 4; // crc
      }

      wUi(data, offset, 0); offset += 4;
      wAs(data, offset, "IEND"); offset += 4;
      wUi(data, offset, crc(data, offset - 4, 4)); offset += 4; // crc

      return data.buffer;
    }

    UPNG.encode.compressPNG = function (out, filter) {
      for (var i = 0; i < out.frames.length; i++) {
        var frm = out.frames[i], nw = frm.rect.width, nh = frm.rect.height;
        var fdata = new Uint8Array(nh * frm.bpl + nh);
        frm.cimg = UPNG.encode._filterZero(frm.img, nh, frm.bpp, frm.bpl, fdata, filter);
      }
    }



    UPNG.encode.compress = function (bufs, w, h, ps, forGIF, forbidPlte) {
      //var time = Date.now();
      if (forbidPlte == null) forbidPlte = false;

      var ctype = 6, depth = 8, alphaAnd = 255

      for (var j = 0; j < bufs.length; j++) {  // when not quantized, other frames can contain colors, that are not in an initial frame
        var img = new Uint8Array(bufs[j]), ilen = img.length;
        for (var i = 0; i < ilen; i += 4) alphaAnd &= img[i + 3];
      }
      var gotAlpha = (alphaAnd != 255);
      var brute = gotAlpha && forGIF;		// brute : frames can only be copied, not "blended"
      var frms = UPNG.encode.framize(bufs, w, h, forGIF, brute);
      var cmap = {}, plte = [], inds = [];
      if (ps != 0) {
        var nbufs = []; for (var i = 0; i < frms.length; i++) nbufs.push(frms[i].img.buffer);

        var abuf = UPNG.encode.concatRGBA(nbufs, forGIF), qres = UPNG.quantize(abuf, ps);
        var cof = 0, bb = new Uint8Array(qres.abuf);
        for (var i = 0; i < frms.length; i++) {
          var ti = frms[i].img, bln = ti.length; inds.push(new Uint8Array(qres.inds.buffer, cof >> 2, bln >> 2));
          for (var j = 0; j < bln; j += 4) { ti[j] = bb[cof + j]; ti[j + 1] = bb[cof + j + 1]; ti[j + 2] = bb[cof + j + 2]; ti[j + 3] = bb[cof + j + 3]; } cof += bln;
        }

        for (var i = 0; i < qres.plte.length; i++) plte.push(qres.plte[i].est.rgba);
      }
      else {
        // what if ps==0, but there are <=256 colors?  we still need to detect, if the palette could be used
        for (var j = 0; j < frms.length; j++) {  // when not quantized, other frames can contain colors, that are not in an initial frame
          var frm = frms[j], img32 = new Uint32Array(frm.img.buffer), nw = frm.rect.width, ilen = img32.length;
          var ind = new Uint8Array(ilen); inds.push(ind);
          for (var i = 0; i < ilen; i++) {
            var c = img32[i];
            if (i != 0 && c == img32[i - 1]) ind[i] = ind[i - 1];
            else if (i > nw && c == img32[i - nw]) ind[i] = ind[i - nw];
            else {
              var cmc = cmap[c];
              if (cmc == null) { cmap[c] = cmc = plte.length; plte.push(c); if (plte.length >= 300) break; }
              ind[i] = cmc;
            }
          }
        }
      }

      var cc = plte.length;
      if (cc <= 256 && forbidPlte == false) {
        if (cc <= 2) depth = 1; else if (cc <= 4) depth = 2; else if (cc <= 16) depth = 4; else depth = 8;
        if (forGIF) depth = 8;
      }

      for (var j = 0; j < frms.length; j++) {
        var frm = frms[j], nx = frm.rect.x, ny = frm.rect.y, nw = frm.rect.width, nh = frm.rect.height;
        var cimg = frm.img, cimg32 = new Uint32Array(cimg.buffer);
        var bpl = 4 * nw, bpp = 4;
        if (cc <= 256 && forbidPlte == false) {
          bpl = Math.ceil(depth * nw / 8);
          var nimg = new Uint8Array(bpl * nh);
          var inj = inds[j];
          for (var y = 0; y < nh; y++) {
            var i = y * bpl, ii = y * nw;
            if (depth == 8) for (var x = 0; x < nw; x++) nimg[i + (x)] = (inj[ii + x]);
            else if (depth == 4) for (var x = 0; x < nw; x++) nimg[i + (x >> 1)] |= (inj[ii + x] << (4 - (x & 1) * 4));
            else if (depth == 2) for (var x = 0; x < nw; x++) nimg[i + (x >> 2)] |= (inj[ii + x] << (6 - (x & 3) * 2));
            else if (depth == 1) for (var x = 0; x < nw; x++) nimg[i + (x >> 3)] |= (inj[ii + x] << (7 - (x & 7) * 1));
          }
          cimg = nimg; ctype = 3; bpp = 1;
        }
        else if (gotAlpha == false && frms.length == 1) {	// some next "reduced" frames may contain alpha for blending
          var nimg = new Uint8Array(nw * nh * 3), area = nw * nh;
          for (var i = 0; i < area; i++) { var ti = i * 3, qi = i * 4; nimg[ti] = cimg[qi]; nimg[ti + 1] = cimg[qi + 1]; nimg[ti + 2] = cimg[qi + 2]; }
          cimg = nimg; ctype = 2; bpp = 3; bpl = 3 * nw;
        }
        frm.img = cimg; frm.bpl = bpl; frm.bpp = bpp;
      }

      return { ctype: ctype, depth: depth, plte: plte, frames: frms };
    }
    UPNG.encode.framize = function (bufs, w, h, forGIF, brute) {
      var frms = [];
      for (var j = 0; j < bufs.length; j++) {
        var cimg = new Uint8Array(bufs[j]), cimg32 = new Uint32Array(cimg.buffer);

        var nx = 0, ny = 0, nw = w, nh = h, blend = 0;
        if (j != 0 && !brute) {
          var tlim = (forGIF || j == 1 || frms[frms.length - 2].dispose == 2) ? 1 : 2, tstp = 0, tarea = 1e9;
          for (var it = 0; it < tlim; it++) {
            var pimg = new Uint8Array(bufs[j - 1 - it]), p32 = new Uint32Array(bufs[j - 1 - it]);
            var mix = w, miy = h, max = -1, may = -1;
            for (var y = 0; y < h; y++) for (var x = 0; x < w; x++) {
              var i = y * w + x;
              if (cimg32[i] != p32[i]) {
                if (x < mix) mix = x; if (x > max) max = x;
                if (y < miy) miy = y; if (y > may) may = y;
              }
            }
            var sarea = (max == -1) ? 1 : (max - mix + 1) * (may - miy + 1);
            if (sarea < tarea) {
              tarea = sarea; tstp = it;
              if (max == -1) { nx = ny = 0; nw = nh = 1; }
              else { nx = mix; ny = miy; nw = max - mix + 1; nh = may - miy + 1; }
            }
          }

          var pimg = new Uint8Array(bufs[j - 1 - tstp]);
          if (tstp == 1) frms[frms.length - 1].dispose = 2;

          var nimg = new Uint8Array(nw * nh * 4), nimg32 = new Uint32Array(nimg.buffer);
          UPNG._copyTile(pimg, w, h, nimg, nw, nh, -nx, -ny, 0);
          if (UPNG._copyTile(cimg, w, h, nimg, nw, nh, -nx, -ny, 3)) {
            UPNG._copyTile(cimg, w, h, nimg, nw, nh, -nx, -ny, 2); blend = 1;
          }
          else {
            UPNG._copyTile(cimg, w, h, nimg, nw, nh, -nx, -ny, 0); blend = 0;
          }
          cimg = nimg;
        }
        else cimg = cimg.slice(0);	// img may be rewrited further ... don't rewrite input
        frms.push({ rect: { x: nx, y: ny, width: nw, height: nh }, img: cimg, blend: blend, dispose: brute ? 1 : 0 });
      }
      return frms;
    }

    UPNG.encode._filterZero = function (img, h, bpp, bpl, data, filter) {
      if (filter != -1) {
        for (var y = 0; y < h; y++) UPNG.encode._filterLine(data, img, y, bpl, bpp, filter);
        return pako["deflate"](data);
      }
      var fls = [];
      for (var t = 0; t < 5; t++) {
        if (h * bpl > 500000 && (t == 2 || t == 3 || t == 4)) continue;
        for (var y = 0; y < h; y++) UPNG.encode._filterLine(data, img, y, bpl, bpp, t);
        fls.push(pako["deflate"](data)); if (bpp == 1) break;
      }
      var ti, tsize = 1e9;
      for (var i = 0; i < fls.length; i++) if (fls[i].length < tsize) { ti = i; tsize = fls[i].length; }
      return fls[ti];
    }
    UPNG.encode._filterLine = function (data, img, y, bpl, bpp, type) {
      var i = y * bpl, di = i + y, paeth = UPNG.decode._paeth
      data[di] = type; di++;

      if (type == 0) for (var x = 0; x < bpl; x++) data[di + x] = img[i + x];
      else if (type == 1) {
        for (var x = 0; x < bpp; x++) data[di + x] = img[i + x];
        for (var x = bpp; x < bpl; x++) data[di + x] = (img[i + x] - img[i + x - bpp] + 256) & 255;
      }
      else if (y == 0) {
        for (var x = 0; x < bpp; x++) data[di + x] = img[i + x];

        if (type == 2) for (var x = bpp; x < bpl; x++) data[di + x] = img[i + x];
        if (type == 3) for (var x = bpp; x < bpl; x++) data[di + x] = (img[i + x] - (img[i + x - bpp] >> 1) + 256) & 255;
        if (type == 4) for (var x = bpp; x < bpl; x++) data[di + x] = (img[i + x] - paeth(img[i + x - bpp], 0, 0) + 256) & 255;
      }
      else {
        if (type == 2) { for (var x = 0; x < bpl; x++) data[di + x] = (img[i + x] + 256 - img[i + x - bpl]) & 255; }
        if (type == 3) {
          for (var x = 0; x < bpp; x++) data[di + x] = (img[i + x] + 256 - (img[i + x - bpl] >> 1)) & 255;
          for (var x = bpp; x < bpl; x++) data[di + x] = (img[i + x] + 256 - ((img[i + x - bpl] + img[i + x - bpp]) >> 1)) & 255;
        }
        if (type == 4) {
          for (var x = 0; x < bpp; x++) data[di + x] = (img[i + x] + 256 - paeth(0, img[i + x - bpl], 0)) & 255;
          for (var x = bpp; x < bpl; x++) data[di + x] = (img[i + x] + 256 - paeth(img[i + x - bpp], img[i + x - bpl], img[i + x - bpp - bpl])) & 255;
        }
      }
    }

    UPNG.crc = {
      table: (function () {
        var tab = new Uint32Array(256);
        for (var n = 0; n < 256; n++) {
          var c = n;
          for (var k = 0; k < 8; k++) {
            if (c & 1) c = 0xedb88320 ^ (c >>> 1);
            else c = c >>> 1;
          }
          tab[n] = c;
        }
        return tab;
      })(),
      update: function (c, buf, off, len) {
        for (var i = 0; i < len; i++)  c = UPNG.crc.table[(c ^ buf[off + i]) & 0xff] ^ (c >>> 8);
        return c;
      },
      crc: function (b, o, l) { return UPNG.crc.update(0xffffffff, b, o, l) ^ 0xffffffff; }
    }


    UPNG.quantize = function (abuf, ps) {
      var oimg = new Uint8Array(abuf), nimg = oimg.slice(0), nimg32 = new Uint32Array(nimg.buffer);

      var KD = UPNG.quantize.getKDtree(nimg, ps);
      var root = KD[0], leafs = KD[1];

      var planeDst = UPNG.quantize.planeDst;
      var sb = oimg, tb = nimg32, len = sb.length;

      var inds = new Uint8Array(oimg.length >> 2);
      for (var i = 0; i < len; i += 4) {
        var r = sb[i] * (1 / 255), g = sb[i + 1] * (1 / 255), b = sb[i + 2] * (1 / 255), a = sb[i + 3] * (1 / 255);

        //  exact, but too slow :(
        var nd = UPNG.quantize.getNearest(root, r, g, b, a);
        //var nd = root;
        //while(nd.left) nd = (planeDst(nd.est,r,g,b,a)<=0) ? nd.left : nd.right;

        inds[i >> 2] = nd.ind;
        tb[i >> 2] = nd.est.rgba;
      }
      return { abuf: nimg.buffer, inds: inds, plte: leafs };
    }

    UPNG.quantize.getKDtree = function (nimg, ps, err) {
      if (err == null) err = 0.0001;
      var nimg32 = new Uint32Array(nimg.buffer);

      var root = { i0: 0, i1: nimg.length, bst: null, est: null, tdst: 0, left: null, right: null };  // basic statistic, extra statistic
      root.bst = UPNG.quantize.stats(nimg, root.i0, root.i1); root.est = UPNG.quantize.estats(root.bst);
      var leafs = [root];

      while (leafs.length < ps) {
        var maxL = 0, mi = 0;
        for (var i = 0; i < leafs.length; i++) if (leafs[i].est.L > maxL) { maxL = leafs[i].est.L; mi = i; }
        if (maxL < err) break;
        var node = leafs[mi];

        var s0 = UPNG.quantize.splitPixels(nimg, nimg32, node.i0, node.i1, node.est.e, node.est.eMq255);
        var s0wrong = (node.i0 >= s0 || node.i1 <= s0);
        if (s0wrong) { node.est.L = 0; continue; }


        var ln = { i0: node.i0, i1: s0, bst: null, est: null, tdst: 0, left: null, right: null }; ln.bst = UPNG.quantize.stats(nimg, ln.i0, ln.i1);
        ln.est = UPNG.quantize.estats(ln.bst);
        var rn = { i0: s0, i1: node.i1, bst: null, est: null, tdst: 0, left: null, right: null }; rn.bst = { R: [], m: [], N: node.bst.N - ln.bst.N };
        for (var i = 0; i < 16; i++) rn.bst.R[i] = node.bst.R[i] - ln.bst.R[i];
        for (var i = 0; i < 4; i++) rn.bst.m[i] = node.bst.m[i] - ln.bst.m[i];
        rn.est = UPNG.quantize.estats(rn.bst);

        node.left = ln; node.right = rn;
        leafs[mi] = ln; leafs.push(rn);
      }
      leafs.sort(function (a, b) { return b.bst.N - a.bst.N; });
      for (var i = 0; i < leafs.length; i++) leafs[i].ind = i;
      return [root, leafs];
    }

    UPNG.quantize.getNearest = function (nd, r, g, b, a) {
      if (nd.left == null) { nd.tdst = UPNG.quantize.dist(nd.est.q, r, g, b, a); return nd; }
      var planeDst = UPNG.quantize.planeDst(nd.est, r, g, b, a);

      var node0 = nd.left, node1 = nd.right;
      if (planeDst > 0) { node0 = nd.right; node1 = nd.left; }

      var ln = UPNG.quantize.getNearest(node0, r, g, b, a);
      if (ln.tdst <= planeDst * planeDst) return ln;
      var rn = UPNG.quantize.getNearest(node1, r, g, b, a);
      return rn.tdst < ln.tdst ? rn : ln;
    }
    UPNG.quantize.planeDst = function (est, r, g, b, a) { var e = est.e; return e[0] * r + e[1] * g + e[2] * b + e[3] * a - est.eMq; }
    UPNG.quantize.dist = function (q, r, g, b, a) { var d0 = r - q[0], d1 = g - q[1], d2 = b - q[2], d3 = a - q[3]; return d0 * d0 + d1 * d1 + d2 * d2 + d3 * d3; }

    UPNG.quantize.splitPixels = function (nimg, nimg32, i0, i1, e, eMq) {
      var vecDot = UPNG.quantize.vecDot;
      i1 -= 4;
      var shfs = 0;
      while (i0 < i1) {
        while (vecDot(nimg, i0, e) <= eMq) i0 += 4;
        while (vecDot(nimg, i1, e) > eMq) i1 -= 4;
        if (i0 >= i1) break;

        var t = nimg32[i0 >> 2]; nimg32[i0 >> 2] = nimg32[i1 >> 2]; nimg32[i1 >> 2] = t;

        i0 += 4; i1 -= 4;
      }
      while (vecDot(nimg, i0, e) > eMq) i0 -= 4;
      return i0 + 4;
    }
    UPNG.quantize.vecDot = function (nimg, i, e) {
      return nimg[i] * e[0] + nimg[i + 1] * e[1] + nimg[i + 2] * e[2] + nimg[i + 3] * e[3];
    }
    UPNG.quantize.stats = function (nimg, i0, i1) {
      var R = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
      var m = [0, 0, 0, 0];
      var N = (i1 - i0) >> 2;
      for (var i = i0; i < i1; i += 4) {
        var r = nimg[i] * (1 / 255), g = nimg[i + 1] * (1 / 255), b = nimg[i + 2] * (1 / 255), a = nimg[i + 3] * (1 / 255);
        //var r = nimg[i], g = nimg[i+1], b = nimg[i+2], a = nimg[i+3];
        m[0] += r; m[1] += g; m[2] += b; m[3] += a;

        R[0] += r * r; R[1] += r * g; R[2] += r * b; R[3] += r * a;
        R[5] += g * g; R[6] += g * b; R[7] += g * a;
        R[10] += b * b; R[11] += b * a;
        R[15] += a * a;
      }
      R[4] = R[1]; R[8] = R[2]; R[9] = R[6]; R[12] = R[3]; R[13] = R[7]; R[14] = R[11];

      return { R: R, m: m, N: N };
    }
    UPNG.quantize.estats = function (stats) {
      var R = stats.R, m = stats.m, N = stats.N;

      // when all samples are equal, but N is large (millions), the Rj can be non-zero ( 0.0003.... - precission error)
      var m0 = m[0], m1 = m[1], m2 = m[2], m3 = m[3], iN = (N == 0 ? 0 : 1 / N);
      var Rj = [
        R[0] - m0 * m0 * iN, R[1] - m0 * m1 * iN, R[2] - m0 * m2 * iN, R[3] - m0 * m3 * iN,
        R[4] - m1 * m0 * iN, R[5] - m1 * m1 * iN, R[6] - m1 * m2 * iN, R[7] - m1 * m3 * iN,
        R[8] - m2 * m0 * iN, R[9] - m2 * m1 * iN, R[10] - m2 * m2 * iN, R[11] - m2 * m3 * iN,
        R[12] - m3 * m0 * iN, R[13] - m3 * m1 * iN, R[14] - m3 * m2 * iN, R[15] - m3 * m3 * iN
      ];

      var A = Rj, M = UPNG.M4;
      var b = [0.5, 0.5, 0.5, 0.5], mi = 0, tmi = 0;

      if (N != 0)
        for (var i = 0; i < 10; i++) {
          b = M.multVec(A, b); tmi = Math.sqrt(M.dot(b, b)); b = M.sml(1 / tmi, b);
          if (Math.abs(tmi - mi) < 1e-9) break; mi = tmi;
        }
      //b = [0,0,1,0];  mi=N;
      var q = [m0 * iN, m1 * iN, m2 * iN, m3 * iN];
      var eMq255 = M.dot(M.sml(255, q), b);

      return {
        Cov: Rj, q: q, e: b, L: mi, eMq255: eMq255, eMq: M.dot(b, q),
        rgba: (((Math.round(255 * q[3]) << 24) | (Math.round(255 * q[2]) << 16) | (Math.round(255 * q[1]) << 8) | (Math.round(255 * q[0]) << 0)) >>> 0)
      };
    }
    UPNG.M4 = {
      multVec: function (m, v) {
        return [
          m[0] * v[0] + m[1] * v[1] + m[2] * v[2] + m[3] * v[3],
          m[4] * v[0] + m[5] * v[1] + m[6] * v[2] + m[7] * v[3],
          m[8] * v[0] + m[9] * v[1] + m[10] * v[2] + m[11] * v[3],
          m[12] * v[0] + m[13] * v[1] + m[14] * v[2] + m[15] * v[3]
        ];
      },
      dot: function (x, y) { return x[0] * y[0] + x[1] * y[1] + x[2] * y[2] + x[3] * y[3]; },
      sml: function (a, y) { return [a * y[0], a * y[1], a * y[2], a * y[3]]; }
    }

    UPNG.encode.concatRGBA = function (bufs, roundAlpha) {
      var tlen = 0;
      for (var i = 0; i < bufs.length; i++) tlen += bufs[i].byteLength;
      var nimg = new Uint8Array(tlen), noff = 0;
      for (var i = 0; i < bufs.length; i++) {
        var img = new Uint8Array(bufs[i]), il = img.length;
        for (var j = 0; j < il; j += 4) {
          var r = img[j], g = img[j + 1], b = img[j + 2], a = img[j + 3];
          if (roundAlpha) a = (a & 128) == 0 ? 0 : 255;
          if (a == 0) r = g = b = 0;
          nimg[noff + j] = r; nimg[noff + j + 1] = g; nimg[noff + j + 2] = b; nimg[noff + j + 3] = a;
        }
        noff += il;
      }
      return nimg.buffer;
    }








  })(UPNG, pako);
})();

